Apparatus having rotating bushing for forming fibers

ABSTRACT

Apparatus is provided for forming fibers from a heat-softenable, filament-forming viscous liquid. A bushing is in the form of a hollow, cylindrical, rotating body having a spirally contoured outer surface, with a right-hand helix at one end and a left-hand helix at the other end, and with inlet openings spaced around an intermediate portion. Means are provided at one end to rotate the bushing and orifices are provided at the other end through which fibers are attenuated. The bushing is located in a liquid-filled chamber, the liquid being fed under pressure by the helixes to the inlet openings where it is forced inwardly and subsequently subdivided into fibers through the orifices. The orifices can be located in a circular pattern to form a hollow cone of fibers attenuated therefrom, with means located below the center of the circular pattern for supplying a coating material to the filaments or for feeding a filamentary core to the center of the collected filaments.

United States Patent Inventor Robe" Russell Primary ExaminerS. LeonBashore Granville, Ohio Assistant ExaminerRobert L. Lindsay, l r.

PP 829,631 AttorneysStaelin and Overman and Allen D. Gutchess, .lr.

Filed June 2, 1969 Patented Dec. 21, 1971 Assignee Owens-CorningFiberglas Corporation ABSTRACT: Apparatus is provided for forming fibersfrom a heat-softenable, filament-forming viscous liquid. A bushing is inthe form of a hollow, cylindrical, rotating body having a APPARATUSHAVING ROTATING BUSHING FOR spirally contoured outer surface, with aright-hand helix at one FORMING FIBERS end and a left-hand helix at theother end, and with inlet clalms4nl'awlng openings spaced around anintermediate portion. Means are U s provided at one end to rotate thebushing and orifices are pro- [52} 65/11 W, 18/8 R, 1818 SR, 65/2,264/8, 264/176 F vided at the other end through which fibers areattenuated. [5]] C031 37/02 The bushing is located in a liquid-filledchamber, the liquid 50 Field 264/8, 176 being fed under Pressure y thehelixes w the inlet openings where it is forced inwardly andsubsequently subdivided into fibers through the orifices. The orificescan be located in a cir- [56] References Cited cular pattern to form ahollow cone of fibers attenuated UNITED STATES PATENTS therefrom, withmeans located below the center of the circular 2,719,350 10/1955 Slayteretal..................

pattern for supplying a coating material to the filaments or for I 65/8feeding a filamentary core to the center of the collected fila- X ments.65/ 1 low X 5/1962 Slayter et al. $525,785 3,250,602

8/1970 Fairbanks...... 5/ 1966 Stalego PATENIEU 01-3021 um SHEET 1 [1? 2IN VE N TOR. 055 4 7 6 #0555 .4 TTORYEYS APPARATUS HAVING ROTATINGBUSHING FOR FORMING FIBERS This invention relates to apparatus forhandling fluids and more particularly to apparatus for forming fibersfrom heatsofienable, filament forming, viscous liquid.

In apparatus for forming glass fibers, high temperatures must beemployed to render the glass sufficiently fluid to enable the glass tobe divided into a multiplicity of streams and attenuated into fibers.Consequently, because of the high temperatures, highly refractory,costly metals have had to be used in the fiber-forming bushing. However,it has been found that if the glass is maintained at a lowertemperature, where it is more viscous, it can still be attenuated intofibers if fed through the orifices under pressure. Further, with thelower temperatures, less highly refractory and less expensive metals canbe employed.

The present invention relates to unique apparatus for handling liquidsand particularly for forming fibers from viscous liquid under pressure.The new apparatus includes a cylindrical bushing having a plurality ofintermediate inlet openings peripherally spaced therearound with amultiplicity of orifices preferably located in a circular pattern in alower end wall of the bushing. Means are provided at the opposite end ofthe bushing for rotating same. On the outer surface of the bushing are apair of helical flanges or ridges directed with opposite lead angles soas to force liquid in opposite directions when the bushing is rotated.The bushing is located in a liquid chamber to which liquid is suppliedby suitable means and is rotated in a manner such that the liquid atopposite ends of the bushing is forced toward the center and through theperipheral inlet openings to the interior of the bushing. With thecircular pattern of the orifices and rotation of the bushing, means canbe centrally located below the orifices for supply ing liquid coatingmaterial of various types to the fibers. In place of the liquid coatingapplicator, means can be provided, for example, to supply a continuousfibrous or filamentary core of a difierent nature through the center ofthe fiber pattern.

It is, therefore, a principal object of the invention to provideimproved fiber-forming apparatus having the features and advantagesoutlined and discussed above.

Other objects and advantages of the invention will be apparent from thefollowing detailed description of preferred embodiments thereof,reference being made to the accompanying drawings, in which:

FIG. I is a somewhat schematic, fragmentary view in vertical crosssection, with some parts in elevation, of apparatus for forming fibersaccording to the invention;

FIG. 2 is a view in transverse cross section taken along the line 2-2 ofFIG. 1;

FIG. 3 is a cross-sectional view similar to FIG. I of modifiedfiber-forming apparatus; and

FIG. 4 is a fragmentary, sectional view of further modifiedfiber-fonning apparatus.

Referring to FIG. 1, apparatus in accordance with the invention forfeeding liquid and for forming fibers therefrom is indicated at 10. Theapparatus includes a hollow, cylindrical bushing 12 located in a chamber14 to which molten glass is supplied from a source 16. Filaments 18 areattenuated from the bushing 12 in a fan or cone 20. The filaments 18 areled around an idler or gathering shoe 22 and wound on a collet 24supported and rotated by a stand 26 and spread along the collet by alevel wind device 28, all of which is known in the art.

The bushing 12 includes a cylindrical wall 30, an upper end wall 32, anda lower end wall 34. The lower end wall 34 has a multiplicity oforifices 36 therein which, in this instance, are uniformly spaced oversubstantially the entire end wall 34. The cylindrical wall 30 of thebushing has an upper helical ridge or flange 38 and a lower helicalridge or flange 40. These extend from points near the ends of thecylindrical wall 30 to points near the middle of the wall 30,terminating near a plurality of circumferentially spaced inlet openings42.

A central drive shaft 44 is affixed to the upper end wall 32 and extendsupwardly above the apparatus to a pair of spaced bearings 46 attached tosuitable supports 48. A drive pulley 50 is located between the bearings46 to rotate the shaft 44 and the bushing 12. When the bushing isrotated in a predetermined direction, glass or other viscous liquidlocated in the chamber 14 around the bushing 12 is forced by the helicalflanges 38 and 40 from end portions of the bushing toward the center andinto the inlet openings 42. The flanges 38 and 40 are spaced somewhatfrom the wall of the chamber 14 so that if pressure of the glass in thebushing 12 becomes excessive, part of the glass can flow back toward theends of the bushing outside the flanges.

The rate of rotation of the bushing will depend on the output of glassthrough the orifices 36 and will also vary with the viscosity of theglass. The rate of rotation is controlled so that the rate at which theglass is carried to the openings 42 tends to exceed the rate at whichthe filaments 18 are attenuated from the end wall 34 with the resultthat the glass in he bushing 12 is maintained under a constant pressure.This enables the glass to be attenuated through the orifices 36 at alower temperature than otherwise required and enables the bushing 12 tobe made of relatively lower cost metals, rather than the platinum alloysrequired at higher temperatures. Further, the orifices 36 can be smallerthan otherwise, with the result that more can be employed in a givenspace. Consequently, a given number of filaments can be produced from asmaller bushing and associated apparatus than otherwise required. Thisenables a reduction in the size of the overall apparatus, resulting insavings in materials and operating expenses, as well as overall spacerequirements.

The rotating cylindrical wall 30 and the flanges 38 and 40 alsosignificantly aid in mixing the glass as it is carried to the inletopenings 42. This eliminates any chords in the glass and increaseshomogeneity.

The source 16 of glass or other liquid can be in the form of a tank ofthe liquid heated by suitable means (not shown). The glass is suppliedto the chamber 14 from the source 16 through a pair of flow controldevices 52 and 54. The upper flow control device 52 includes anextension 56 of the chamber wall fonning a passage 58 and a valve seat60. An externally adjustable needle valve 62 cooperates with the seat 60to vary the opening into the passage 58 and, therefore, the flow ofglass into the chamber 14. By restricting this flow, a reduced pressureof the glass in the upper part of the chamber 14 is established toeliminate any possibility of glass leaking through a cylindrical upperopening 64 through which the shaft 44 extends. The low pressure isestablished because the glass in the upper body is carried downwardly bythe helical flange 38.

The flow control device 54 also includes an extension 66 of the chamber14 forming a passage 68 and a valve seat 70. The valve seat 70cooperates with an externally adjustable needle valve 72 to control flowinto the passage 68 from the source 16. A negative pressure of the glassin the lower part of the chamber 14 also can be established byrestricting the rate of flow past the needle valve 70. The prevention ofleakage of the glass through a lower opening 74 through which the lowerextremity of the bushing 12 extends, also is prevented by a circularring 76 located immediately above the opening 74. The ring 76 rotateswith the bushing and forms a dynamic seal by urging outwardly glassadjacent the ring 76 to keep the glass away from the opening 74.

Referring now to FIG. 3, modified apparatus embodying the invention isindicated at 78. This apparatus is basically similar to that of FIG. 1,but modified to employ a central coating applicator. A modified bushing80 includes a cylindrical side wall 82 with annular end walls 84 and 86connected by a central inner cylindrical wall 88. A hollow drive shaft90 extends upwardly from the upper end wall 84, being supported bybearings 92 and driven by a pulley 94.

In accordance with this embodiment of the invention, a tubular sleeve 96extends downwardly through the hollow drive shaft 90 and the innercylindrical wall 88 to a point below the lower end wall 86. The sleeve96 is provided with a coolant supply tube 98 and a coolant outlet line104) for supplying a suitable coolant to the interior of the sleeve 96.A central coating material supply line 102 extends downwardly throughthe sleeve 96 to a point below a lower end wall 11% of the sleeve to aspray applicator 106. The spray applicator 106 has a plurality ofnozzles 108 therearound which project the coating material outwardlyonto two annular rows of filaments 110 attenuated from two annular rowsof orifices 112 located in the lower annular end wall 86. With thecoolant supplied through the lines 98 and 100, the sleeve 96 ismaintained at a lower temperature and can be made of conventionalmaterials. Also, the coating material and its supply line 102 do notreach excessive temperatures.

With this arrangement, the filaments 110 are uniformly coated by thespray applicator 106 as they are attenuated past the spray nozzles 108and at the same time rotate with the bushing. This provides an efficientand uniform method of coating.

Referring to FIG. 4, a hollow supply member 114 is substituted in thesleeve 96 for the supply line 102 with the supply member extending belowthe lower end wall 104 of the sleeve and located centrally with respectto the bushing 89. A filamentary core material 1 16 is fed through themember 1 l4 and is received centrally therebelow in the core of thefilaments 110 which are wound in a spiral manner in this instance aroundthe core material 116 which aids in attenuating the filaments 110 aswell as constituting a final part of a composite twisted strand 118formed by the core material 116 and the filaments 110. The filamentarymaterial 1116 can be raised to an elevated temperature in the supplymember l 14 by the heat of the bushing so that it is in a softened stateas it exits below the bushing. In this state, it can integrally formwith and par tially envelop the filaments 110 to provide a unitarycomposite without further treatment being required.

If desired, a fiber-forming material can be supplied through the line102 or the member 1 l4. Fibers can then be attenuated from this materialthrough the nozzles or openings 1108 and from the end of the supplymember 114. in such an instance, heated liquid could be supplied throughthe lines 98 and 100 to aid in bringing the fiber-forming materials to aproper fiberfonning temperature, if desired.

lt will be seen from the above that the fiber-forming apparatusaccording to the invention has many advantages. The glass or otherviscous liquid is thoroughly mixed as it is supplied to the bushing. Thebushing is at lower temperatures and can be of relatively low-costmaterials as well as being smaller in size. Further, the coating andcore arrangements of FIGS. 3 and 4 provide additional advantages for thebushing arrange ment of the invention.

Various modifications of the above-described embodiments of theinvention will be apparent to those skilled in the art and it is to beunderstood that such modifications can be made without departing fromthe scope of the invention, the embodiments shown and described beingprimarily for purposes of illustration and not limitation.

I claim:

1 F iber-forming apparatus for feeding a heat-softenable,filament-forming, viscous liquid and for subsequent attenuating theliquid into a multiplicity of fibers, said apparatus comprising ahollow, rotatable body having at least one inlet opening in a wallthereof and a multiplicity of fiber-forming orifices spaced from saidinlet opening in a lower portion of said rotatable body, means forrotating said rotatable body, means forming a chamber around said body,means forming a seal between said chamber-forming means and said body ata lower portion of said body above said orifices, means for supplyingthe liquid to said chamber, means for forcing the liquid in said chamberthrough said opening into said body to maintain the liquid in said bodyunder pressure to aid in forcing the liquid subsequently through saidorifices when said body is rotated, and means for subsequentlyattenuating into fibers the liquid flowing from said orifices.

2. Apparatus according to claim 1 wherein said inlet opening is locatedat an intermediate portion of said body wall and said forcing meanscomprises a pair of helical flanges extending outwardly from the wall ofsaid rotatable body at opposite end portions thereof, said helicalflanges having opposite lead angles whereby liquid near the ends of saidbody is forced toward the intermediate opening in said body as said bodyis rotated.

3. Apparatus according to claim 1 characterized further by said supplymeans including means for supplying the liquid to two spaced portions ofsaid chamber near end portions of said rotatable body.

1. Apparatus according to claim 3 characterized by flow control meansfor controlling the flow of liquid to both of the spaced portions ofsaid chamber.

5. Apparatus according to claim 1 characterized further by said sealcomprising a circular outer flange extending from the lower portion ofsaid body and forming a dynamic seal to prevent passage of the liquidaround said body and out of said chamber.

6. Apparatus according to claim 1 characterized further by said rotatingmeans comprising said rotatable body having an axially positioned shaftat one end thereof extending through said chamber forming means, andmeans located outside said chamber for rotating w d shaft and said body.

7. Apparatus according to claim 1 characterized further by meansextending through said rotatable body and terminating in a coatingmaterial applicator beyond said body, said applicator being effective tosupply coating material to fibers attenuated from the liquid flowingthrough said orifices in said body.

8. Apparatus according to claim 1 characterized further by meansextending centrally through said hollow body for supplying a filamentarycore material centrally through fibers attenuated from said body.

9. Apparatus for controlling and directing a heat-softenable,filament-forming liquid for subsequent subdivision and attenuation intofilaments, said apparatus comprising a hollow bushing having acylindrical wall and a lower end wall, said bushing having an inletopening in an intermediate portion of said cylindrical wall, means forrotating said bushing, means forming a chamber around said bushing,means for supplying said liquid to said chamber, a plurality of orificesin said lower end wall of said bushing, and means in said chamberlocated around said bushing for forcing liquid in said chamber towardand through said inlet opening to maintain the liquid in said bushingunder pressure to aid the flow of the liquid through said orifices.

10. Apparatus according to claim 9 characterized further by saidrotating means comprising a drive shaft affixed to said bushing andextending outside said chamber, and means located outside said chamberfor rotating said shaft and said bushing.

ll. Apparatus according to claim 9 wherein said liquid forcing meanscomprises a pair of helical flanges extending outwardly from the bushingat opposite end portions thereof, said helical flanges having oppositelead angles whereby liquid near the ends of said bushing is forcedtoward the intermediate opening when said bushing is rotated.

12. Apparatus according to claim 9 characterized further by said liquidsupply means includes means for supplying the liquid to two spacedportions of said chamber near end portions of said bushing.

l3. Apparatus according to claim 12 characterized by flow control meansfor controlling the flow of liquid to both of the spaced portions ofsaid chamber.

14. Apparatus according to claim 9 characterized further by an end ofsaid bushing having a circular outer flange extending therefrom abovesaid orifices and forming a dynamic seal to prevent passage of theliquid around said bushing and out of said chamber.

15. Apparatus according to claim 9 characterized further by an innercylindrical wall extending through said bushing and 17. Apparatusaccording to claim 15 characterized further by means extending centrallythrough said inner cylindrical wall of said bushing for supplying afilamentary core material centrally through a cone of filamentsattenuated from said bushing.

l i i l l

2. Apparatus according to claim 1 wherein said inlet opening is locatedat an intermediate portion of said body wall and said forcing meanscomprises a pair of helical flanges extending outwardly from the wall ofsaid rotatable body at opposite end portions thereof, said helicalflanges having opposite lead angles whereby liquid near the ends of saidbody is forced toward the intermediate opening in said body as said bodyis rotated.
 3. Apparatus according to claim 1 characterized further bysaid supply means including means for supplying the liquid to two spacedportions of said chamber near end portions of said rotatable body. 4.Apparatus according to claim 3 characterized by flow control means forcontrolling the flow of liquid to both of the spaced portions of saidchamber.
 5. Apparatus according to claim 1 characterized further by saidseal comprising a circular outer flange extending from the lower portionof said body and forming a dynamic seal to prevent passage of the liquidaround said body and out of said chamber.
 6. Apparatus according toclaim 1 characterized further by said rotating means comprising saidrotatable body having an axially positioned shaft at one end thereofextending through said chamber forming means, and means located outsidesaid chamber for rotating said shaft and said body.
 7. Apparatusaccording to claim 1 characterized further by means extending throughsaid rotatable body and terminating in a coating material applicatorbeyond said body, said applicator being effective to supply coatingmaterial to fibers attenuated from the liquid flowing through saidorifices in said body.
 8. Apparatus according to claim 1 characterizedfurther by means extending centrally through said hollow body forsupplying a filamentary core material centrAlly through fibersattenuated from said body.
 9. Apparatus for controlling and directing aheat-softenable, filament-forming liquid for subsequent subdivision andattenuation into filaments, said apparatus comprising a hollow bushinghaving a cylindrical wall and a lower end wall, said bushing having aninlet opening in an intermediate portion of said cylindrical wall, meansfor rotating said bushing, means forming a chamber around said bushing,means for supplying said liquid to said chamber, a plurality of orificesin said lower end wall of said bushing, and means in said chamberlocated around said bushing for forcing liquid in said chamber towardand through said inlet opening to maintain the liquid in said bushingunder pressure to aid the flow of the liquid through said orifices. 10.Apparatus according to claim 9 characterized further by said rotatingmeans comprising a drive shaft affixed to said bushing and extendingoutside said chamber, and means located outside said chamber forrotating said shaft and said bushing.
 11. Apparatus according to claim 9wherein said liquid forcing means comprises a pair of helical flangesextending outwardly from the bushing at opposite end portions thereof,said helical flanges having opposite lead angles whereby liquid near theends of said bushing is forced toward the intermediate opening when saidbushing is rotated.
 12. Apparatus according to claim 9 characterizedfurther by said liquid supply means includes means for supplying theliquid to two spaced portions of said chamber near end portions of saidbushing.
 13. Apparatus according to claim 12 characterized by flowcontrol means for controlling the flow of liquid to both of the spacedportions of said chamber.
 14. Apparatus according to claim 9characterized further by an end of said bushing having a circular outerflange extending therefrom above said orifices and forming a dynamicseal to prevent passage of the liquid around said bushing and out ofsaid chamber.
 15. Apparatus according to claim 9 characterized furtherby an inner cylindrical wall extending through said bushing and forminga central cylindrical space to receive a central supply member. 16.Apparatus according to claim 15 characterized further by means extendingthrough said inner cylindrical wall of said bushing and terminating in acoating material applicator beyond said bushing, said applicator beingeffective to supply coating material to filaments rotating around saidapplicator.
 17. Apparatus according to claim 15 characterized further bymeans extending centrally through said inner cylindrical wall of saidbushing for supplying a filamentary core material centrally through acone of filaments attenuated from said bushing.